Compact folded camera structure

ABSTRACT

Folded cameras and dual folded-upright cameras that reduce a mobile electronic device and specifically a smartphone bump footprint and height. In some examples, the bump footprint is reduced by reducing the height of a back focal plane section of the folded camera. In some examples, the bump footprint is reduced by reducing the height of a back focal plane section and a lens subsection of the folded camera.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a 371 application for international patentapplication PCT/IB2018/058974 filed Nov. 14, 2018, and claims priorityto U.S. provisional patent applications No. 62/590,324 filed Nov. 23,2017, and No. 62/618,304 filed Jan. 17, 2018, both incorporated hereinby reference in their entirety.

FIELD

Embodiments disclosed herein relate in general to digital cameras and inparticular folded cameras and dual folded-upright cameras incorporatedin mobile electronic devices such as smartphones.

BACKGROUND

In recent years, mobile electronic devices such as cell-phones (and inparticular smartphones), tablets and laptops have become ubiquitous.Many of these devices include one or two compact “upright” camerasincluding, for example, a main rear-facing camera (i.e. a camera on theback side of the device, facing away from the user and often used forcasual photography) and a secondary front-facing camera (i.e. a cameralocated on the front side of the device and often used for videoconferencing). An important figure of merit in mobile phone cameras andin particular cell phone camera is the camera height or verticaldistance of the camera or camera lens.

Although relatively compact in nature, the design of most of thesecameras is similar to the traditional design of a digital still camera,i.e. it comprises a lens assembly (or a train of several opticalelements) placed on top of an image sensor, which explains the term“upright”. The lens assembly (also referred to as “lens module” orsimply “lens”) refracts the incoming light rays and bends them to createimage data (or an “image”) of a scene on the image sensor. Thedimensions of these cameras are largely determined by the size of thesensor and by the height of the optics. These are usually tied togetherthrough the focal length (“f”) of the lens and its field of view (FOV).That is, a lens that has to image a certain FOV on a sensor of a certainsize has a specific focal length. In such cameras, an increase in thefocal length typically results with an increase of the optics height.

Recently a folded camera structure (also referred to simply as “foldedcamera”) has been suggested to reduce the height of a compact camera(see e.g. co-owned patent applications US 20160044250 andPCT/IB2016/052143, incorporated herein by reference in their entirety).In a folded camera, see FIGS. 1A-1C, an optical path folding element(referred to hereinafter as “OPFE” or “reflecting element”) e.g. a prismor a mirror, is added in order to tilt the light propagation directionfrom substantially perpendicular to the mobile device back surface tosubstantially parallel to the mobile device back surface. Forsimplicity, a reflecting element will henceforth be referred to also as“OPFE”. FIGS. 1A-1C show a known folded camera numbered 100 in variousviews. An orthogonal X-Y-Z coordinate (“axis”) system is shown for theperspective views, FIGS. 1A and 1B. These coordinates apply to allfollowing perspective views. Two of the coordinates are shown separatelyfor the side view, FIG. 1C. These coordinates apply also to allfollowing side views. The coordinate system shown is exemplary.

For the sake of clarity, the term “substantially” is used herein toimply the possibility of variations in values within an acceptablerange. According to one example, the term “substantially” used hereinshould be interpreted to imply possible variation of up to 10% over orunder any specified value. According to another example, the term“substantially” used herein should be interpreted to imply possiblevariation of up to 5% over or under any specified value. According to afurther example, the term “substantially” used herein should beinterpreted to imply possible variation of up to 2.5% over or under anyspecified value.

Camera 100 includes an OPFE section 102 with length L_(P) and heightH_(P), a lens section 104 with length L_(L) and a back focal length(BFL) section 106 with length L_(BFL). In some embodiments, thepartition to several parts is such that each part is fabricatedseparately, and all parts are glued together. In some embodiments, thepartition to several part is only schematic, namely all parts are madeas one in the fabrication process. The three sections have asubstantially common height H_(FL) (within 10% difference or less) whichcorrespond roughly with a “camera height” of the folded camera. H_(FL)is defined as the distance along axis Y (Y being the direction from theobject to the camera, or parallel to first direction 110 introducedbelow) between external surfaces of the three sections, or, in the casethe heights of the three sections are not exactly equal, the distancealong axis Y between the external surfaces of the section with thelargest height. In some examples, the range of values for H_(FL) is 3-8mm. In some examples, the range of values for H_(FL) is 5-6 mm. OPFEsection 102 includes an OPFE 108 that folds an optical path from a firstdirection (optical axis) 110 into a second direction (optical axis) 112.Lens section 104 includes a lens assembly 114 with one or more lenselements having a common optical axis parallel to second direction 112.BFL section 106 includes an image sensor (or simply “sensor”) 116. BFLis equal to the distance between the exit surface (toward the sensor) ofthe lens element facing the sensor and the sensor itself. The foldedcamera has a length L_(FL) and a width W_(FL).

A folded camera may be assembled together with a regular “upright”camera into a dual-camera structure (also referred to herein as a “dualfolded-upright camera” or simply “dual-camera”) in a number of differentways, see e.g. co-owned international patent applicationPCT/IB2015/056004, incorporated herein by reference in its entirety. Oneexample of a dual folded-upright camera is shown in FIGS. 2A-2C. Thesefigures show a folded dual-camera numbered 200 in various views. Foldeddual-camera 200 includes a folded camera 202 similar to camera 100 andan upright camera 204 with a height H_(U) and an optical axis 110′parallel to first direction 110. The distance between optical axis 110′and first direction 110 is defined a baseline of folded dual camera 200.In the particular example shown, the two cameras lie along axis Z. Thedual-camera has a length L_(DC) and a width W_(DC). The width W_(DC) canbe determined by the larger of the widths of the folded and uprightcameras. Note that while in the example the folded and upright camerasare shown aligned along the Z axis, other arrangements, as shown forexample, in co-owned PCT patent application PCT/IB2015/056004(incorporated herein by reference in its entirety), are known andpossible.

Dual-cameras with two upright cameras (also referred to herein as “dualupright-upright cameras”) are known. Their incorporation in mobileelectronic devices such as smartphones is also known, with dualupright-upright camera smartphones being sold commercially. FIG. 3Ashows a known dual upright-upright camera numbered 300 included in asmartphone 302 in a back view. A trend in compact cameras is to allowthe upright camera lens to protrude the top surface of the camera, suchthat the lens alone can have a larger height, while other parts of thecamera are lower. This is often referred to as a “bump”, numbered inFIG. 3A with numeral 304. Bumps above the surface of a smartphone andother mobile electronic devices are undesirable.

The use of light flash (e.g. LED flash) elements (or just “flashelements”) in cameras is known. The positioning of flash elements insidethe “bump” of an upright dual camera is known. FIG. 3B shows a knowndual upright-upright camera numbered 310 included in a smartphone 312 ina back view, having a flash element 318 in the “bump” 314. Having afolded camera with a flash element in the bump is desired. It is desiredto provide folded cameras and dual folded-upright cameras that improveupon the deficiencies of the prior art. It is desired to provide foldedcameras and dual folded-upright cameras with a reduced bump footprint.

SUMMARY

Embodiments disclosed herein teach folded cameras and dualfolded-upright cameras that reduce a mobile electronic device andspecifically a smartphone bump footprint and height. In some examples,the bump footprint is reduced by reducing the height of a back focalplane section of the folded camera. In some examples, the bump footprintis reduced by reducing the height of a back focal plane section and alens subsection of the folded camera.

As mentioned, it is desired to reduce and/or eliminate the surface areaof the bump. It is desired for the bump not to extend past the height ofthe camera.

In some embodiments, there is provided a folded camera comprising anOPFE section including an OPFE for folding an optical path from a firstdirection to a second direction, the OPFE section having a OPFE heightH_(P) in the first direction, a lens section positioned between the OPFEand an image sensor, the lens section having at least one lens sectionheight H_(L) in the first direction, and a BFL section extending betweenthe lens section and the image sensor and having a BFL section heightH_(BFL) in the first direction, wherein H_(BFL)<H_(L).

In some embodiments described above or below, the lens section includestwo subsections, wherein a lens subsection closer to the BFL section hasa height H_(L1)<H_(L).

In some embodiments described above or below, H_(BFL)=H_(L).

In some embodiments described above or below, H_(BFL)≤H_(L1) andH_(BFL)<H_(L).

In some embodiments described above or below, the lens section has awidth W_(L) that fulfills the condition W_(L)>H_(L)>H_(BFL).

In some embodiments described above or below, the BFL section has a topside and a bottom side, wherein the lens section has an optical axisparallel to the second direction and wherein the optical axis in the BFLsection is closer to the top side of the BFL section than to the bottomside of the BFL section.

In some embodiments described above or below, the image sensor ispositioned asymmetrically relative to a board it is mounted on.

In some embodiments described above or below, the top side has aninternal surface structured to prevent stray light from being directedtoward the image sensor.

In some embodiments described above or below, wherein the BFL sectionhas a top side and a bottom side, wherein the lens section, BFL sectionand the image sensor share an optical axis, and wherein the optical axisin the BFL section is closer to the top side than to the bottom side,the positioning of the image sensor is asymmetrically relative to aboard it is mounted on.

In some embodiments described above or below, wherein the top side hasan internal surface structured to prevent stray light from beingdirected toward the image sensor.

In some embodiments described above or below, the folded camera furthercomprises a flash element positioned on the BFL section and having aheight H_(FLASH)≤H_(L).

In some embodiments described above or below, the folded camera furthercomprises a flash element positioned on the lens subsection closer tothe BFL section and having a height H_(FLASH)≤H_(L).

In some embodiments described above or below, the folded camera furthercomprises a flash element positioned partially on the BFL section andpartially on the lens subsection closer to the BFL section and having aheight H_(FLASH)≤H_(L).

In some embodiments described above or below, there are provideddual-aperture cameras comprising a folded camera as described above andbelow, together with an upright camera.

In some embodiments described above or below, the dual-aperture cameracomprises a folded camera and an upright camera sharing a single axis inthe second direction.

In some embodiments, a mobile electronic device comprises a foldedcamera described above or below.

In some embodiments described above or below, the mobile electronicdevice comprises a bump on a surface thereof, wherein the bump surroundsan area including the folded camera and wherein at least one bumpdimension is defined by a folded camera dimension.

In some embodiments, a mobile electronic device comprises adual-aperture camera described above or below.

In some embodiments described above or below, there are provided mobileelectronic devices comprising a folded camera and/or a dual-camera asdescribed above and below. In some embodiments, the mobile electronicdevice is a smartphone. The mobile electronic device may include a bumpon a surface thereof, wherein the bump surrounds an area including thefolded camera and/or an upright camera (for dual-cameras) and wherein atleast one bump dimension is defined by a folded camera or dual-cameradimension.

Some embodiments include a method of manufacturing a folded camera,comprising providing an optical path folding element (OPFE) for foldingan optical path from a first direction to a second direction, the OPFEsection having an OPFE height H_(P) in the first direction, providing aback focal length (BFL) section that includes an image sensor, the BFLsection having a BFL section height H_(BFL) in the first direction,providing a lens section having at least one lens, the lens sectionhaving a lens section height H_(L) in the first direction, arranging thelens section between the BFL section and the OPFE along the firstoptical axis, wherein H_(BFL)<H_(L).

In some embodiments described above or below, the OPFE section has aOPFE section height H_(P) in the first direction, wherein H_(BFL)<H_(P).

In some embodiments described above or below, the lens section has atleast two subsections.

In some embodiments described above or below, a lens subsection closerto the BFL section has a height H_(L1), wherein H_(L1)<H_(L).

In some embodiments described above or below, H_(BFL)≤H_(L1) andH_(BFL)<H_(L).

In some embodiments described above or below, the BFL section has a topside and a bottom side, wherein the lens section has an optical axisparallel to the second direction and wherein the optical axis in the BFLsection is closer to the top side of the BFL section than to the bottomside of the BFL section.

In some embodiments described above or below, the BFL section has a topside and a bottom side, wherein the lens section, BFL section and theimage sensor share an optical axis, and wherein the optical axis in theBFL section is closer to the top side than to the bottom side,positioning the image sensor asymmetrically relative to a board it ismounted on.

In some embodiments described above or below, a method includesasymmetrically placing an image sensor relative to the top and bottom ofthe BFL section.

Some embodiments include a method for reducing the bump footprint of asmartphone, the method comprising: providing a smartphone; attaching thefolded camera of any of the above embodiments to an exterior surface ofthe smartphone, wherein the folded camera reduces the bump footprint ofthe smartphone.

In some embodiments described above or below, the bump footprintincludes a length L_(B1), a width W_(B1), and a height H_(B1), whereinL_(B1) has a range of 5-50 mm, W_(B1) has a range of 1-20 mm and H_(B1)has a range of 0.05-3 mm.

In some embodiments described above or below, the lower height of theBFL section relative to the height of the lens section and/or the OPFEsection enables a shorter bump length L_(B1).

In some embodiments described above or below, a method includesincorporating a flash element into the bump footprint.

As set forth above, each of the embodiments may be used in combinationwith one another, as it is contemplated that various combinations ofembodiments can be merged with one another and are part of the scope ofthe present disclosure.

As used herein, the terms “for example”, “exemplarily”, “such as”, “forinstance” and variants thereof describe non-limiting embodiments of thepresently disclosed subject matter.

BRIEF DESCRIPTION OF THE DRAWINGS

Non-limiting examples of embodiments disclosed herein are describedbelow with reference to figures attached hereto that are listedfollowing this paragraph. Identical structures, elements or parts thatappear in more than one figure may be labeled with the same numeral inthe figures in which they appear. The drawings and descriptions aremeant to illuminate and clarify embodiments disclosed herein, and shouldnot be considered limiting in any way.

FIG. 1A shows a known folded camera in a perspective view;

FIG. 1B shows the folded camera of FIG. 1A in a longitudinal crosssection view;

FIG. 1C shows the folded camera of FIG. 1A in a side view;

FIG. 2A shows a known dual upright-folded camera in a perspective view;

FIG. 2B shows the dual upright-folded camera of FIG. 2A in alongitudinal cross section view;

FIG. 2C shows the dual upright-folded camera of FIG. 2A in a side view;

FIG. 3A shows a known dual upright-upright camera included in asmartphone in a back view;

FIG. 3B shows a known upright-upright camera with flash included in asmartphone in a back view;

FIG. 4A shows a dual folded-upright camera of FIGS. 1A-1C included in asmartphone in a perspective view, according to an exemplary embodimentdisclosed herein;

FIG. 4B shows a cross section with enlarged details of the dual-cameraand the smartphone of FIG. 4A;

FIG. 5A shows a folded camera in a perspective view according to anotherexemplary embodiment disclosed herein;

FIG. 5B shows the folded camera of FIG. 5A in a longitudinal crosssection view;

FIG. 5C shows the folded camera of FIG. 5A in a side view;

FIG. 6A shows a dual folded-upright camera in a perspective viewaccording to another exemplary embodiment disclosed herein;

FIG. 6B shows the dual folded-upright camera of FIG. 6A in alongitudinal cross section view;

FIG. 6C shows the dual folded-upright camera of FIG. 6A in a side view;

FIG. 7A shows the dual folded-upright camera of FIGS. 6A-6C included ina smartphone in a perspective view, according to an exemplary embodimentdisclosed herein;

FIG. 7B shows a cross section with enlarged details of the dualfolded-upright camera and the smartphone of FIG. 7A;

FIG. 8A shows a folded camera image sensor mounted on a board of afolded camera as in FIGS. 4A, 4B;

FIG. 8B shows a known folded camera image sensor mounted a board of afolded camera as in FIGS. 6A, 6B;

FIG. 9A shows a folded camera in a perspective view according to anotherexemplary embodiment disclosed herein;

FIG. 9B shows the folded camera of FIG. 9A in a longitudinal crosssection view;

FIG. 9C shows the folded camera of FIG. 9A in a side view;

FIG. 10A shows a dual folded-upright camera in a perspective viewaccording to another exemplary embodiment disclosed herein;

FIG. 10B shows the dual folded-upright camera of FIG. 10A in alongitudinal cross section view;

FIG. 10C shows the dual folded-upright camera of FIG. 10A in a sideview;

FIG. 11A shows the dual folded-upright camera of FIGS. 10A-10C includedin a smartphone in a perspective view, according to an exemplaryembodiment disclosed herein;

FIG. 11B shows a cross section with enlarged details of the dualfolded-upright camera and the smartphone of FIG. 11A.

FIG. 12A shows a folded camera with a flash element in a perspectiveview according to an exemplary embodiment disclosed herein;

FIG. 12B shows the folded camera of FIG. 12A in a longitudinal crosssection view;

FIG. 13A shows a dual folded-upright camera with a folded camera as inFIG. 12 in a perspective view according to an exemplary embodimentdisclosed herein;

FIG. 13B shows a dual folded-upright camera with a folded camera as inFIG. 12 in a perspective view according to another exemplary embodimentdisclosed herein;

FIG. 14A shows a folded camera as in FIG. 9 with a flash element in aperspective view according to an exemplary embodiment disclosed herein;

FIG. 14B shows a folded camera as in FIG. 9 with a flash element in aperspective view according to another exemplary embodiment disclosedherein;

FIG. 14C shows a folded camera as in FIG. 9 with a flash element in aperspective view according to yet another exemplary embodiment disclosedherein;

FIG. 15A shows a dual folded-upright camera with a folded camera as inFIG. 14 in a perspective view according to an exemplary embodimentdisclosed herein;

FIG. 15B shows the dual folded-upright camera of FIG. 15A in a sideview.

DETAILED DESCRIPTION

Folded cameras described herein comprise an optical path folding element(OPFE), a lens and an image sensor. Folded cameras may further includeother parts required for operation, including a focusing mechanism, anoptical image stabilization (OIS) mechanism, a zooming mechanism, amechanical shield, an infra-red (IR) filter, electronics to operatefocusing, a gyroscope, a shutter and/or other parts. Folded cameras mayfurther include additional optical elements between the OPFE and theobject to be photographed. The lens of folded cameras described hereinmay have constant focal length, or may have varying focal length (alsoknown as “zoom lens”).

A folded camera height is generally smaller than the height of anupright camera with a similar effective focal length (EFL). The decreasein the folded cameras height results from the fact that the foldedcamera height is not dependent on the lens height, which is correlatedwith the lens focal length. In an upright camera, its height isdependent on the lens height. Therefore, the lens focal length may beincreased without sacrifice in the camera module height. However, thefolded camera height is determined by lens assembly height and theheight of other parts of the camera, for example an actuator (e.g. anactuator used to shift the lens for focus and\or optical imagestabilization) and a shield height, and cannot be reduced beyond acertain minimum value, without sacrificing optical performance. Ingeneral, the height of folded cameras according to presently disclosedsubject matter may be in the range of 3-8 mm.

It is desirable that smartphones and other mobile electronic deviceshaving cameras with one (or more) folded camera(s) and/or one (or more)upright camera(s) have a bump footprint (width and length) as small aspossible. Independently, it would be desirable in such smartphonesand/or mobile electronic devices to have a bump height as small aspossible

FIG. 4A shows a smartphone 400 comprising a dual folded-upright camerasimilar to camera 200 in a perspective view, according to an exemplaryembodiment disclosed herein. FIG. 4B shows enlarged details of thedual-camera and the smartphone in a cross-section A-A. A bump 404generally surrounding the dual-camera section protrudes above a surfaceof smartphone 402. The bump has a length L_(B1), a width W_(B1), and aheight H_(B1). In some examples L_(B1) has a range of 5-50 mm, W_(B1)has a range of 1-20 mm and H_(B1) has a range of 0.05-3 mm. While itsedges are shown as sharp, they are preferably rounded as in the bump ofFIG. 3. By positioning the folded and upright cameras in a line (along asingle axis), one can obtain a smaller bump footprint than, for example,positioning the folded and upright cameras in an arrangement in whichthe two do not share the same single axis. Note that everywhere exceptin the region of the bump, the phone has a thickness (height) betweenexternal surfaces H_(Phone). In the region of the bump, the phonethickness is larger and marked H_(PB).

The present inventors have found that the dimensions of a bump thataccommodates a dual folded-upright camera may further be reduced byjudicious design of the folded camera.

FIGS. 5A-5C show, in various views, a folded camera structure numbered500 according to an exemplary embodiment disclosed herein. Like camera100, camera 500 includes an OPFE section 502 with length L_(P) and widthW_(P), a lens section 504 with length L_(L) and width W_(L) and a backfocal length (BFL) section 506 with length L_(BFL) and width W_(BFL).Camera 500 may have a height H_(FL), a length L_(FL) and a width W_(FL)similar to that of camera 100. L_(FL) is defined by the sum ofL_(P)+L_(L)+L_(BFL). L_(P) could basically be defined by the reflectingelement height (for example a prism). In some examples according topresently disclosed subject matter, H_(FL) is in the range of 3-8 mm,L_(FL) is in the range of 10-30 mm and W_(FL) is in the range of 3-15mm. Note that the width of different folded camera sections may bedifferent from each other and from W_(FL). These camera height, lengthand width dimensions apply in following disclosed embodiments even ifnot shown in figures.

Camera 500 may include other components with respective functionalitiessimilar to or identical with the components of camera 100. Therefore,these components and their respective functionalities are not describedin detail. Further, camera 500 may include two BFL sections or a splitBFL section. Unlike in camera 100, BFL section 506 in camera 500 has aheight H_(BFL) that is smaller than the height of the lens section H_(L)and a height of the OPFE (for example a prism) section H_(P). Forexample, H_(BFL) may be smaller than H_(L) by 0.05-3 mm. The reductionin height is expressed at a “shoulder” 508. In some examples, H_(L) andH_(P) may be substantially equal (up to 5% difference). In otherexamples, H_(L) may be smaller than H_(P). In some embodiments, camera500 may have a lens section width W_(L) which is larger than the lenssection height H_(L). In some embodiments, W_(L) may be equal to H_(L).In some embodiments, a lens accommodated in the lens section may have ashape with radial symmetry (for example a cylindrical shape). In someembodiments, a lens accommodated in the lens section may have shapewhich does not have radial symmetry (for example a rectangular shape, acylinder with chamfers, etc.).

Camera 500 can be included together with an upright camera 204 in adual-camera 600 as shown in FIGS. 6A-6C. In the case of dual-camera,each of the two cameras may be called a “sub camera”. In some examples,upright camera may have an optical axis 110′ which is parallel to thefirst direction 110. The distance between optical axis 110′ and firstdirection 110 is defined a baseline of folded dual-camera 600. In someexamples, the length L_(DC) and width W_(DC) of dual-camera 600 remainsimilar to those of dual-camera 200. However, dual-camera 600 has alower height H_(BFL) in the BFL section 506 of the folded camera.Therefore, when dual-camera 600 is incorporated in a mobile device suchas a smartphone 700, the lower height of the BFL section enables ashorter bump length.

FIG. 7A shows the dual folded-upright camera of FIGS. 6A-6C included ina smartphone 700 in a perspective view. FIG. 7B shows a cross sectionwith enlarged details of the dual folded-upright camera and thesmartphone. Smartphone 700 has a bump 604 protruding over a surface 602.Bump 604 has a length L_(B2) and a height H_(B2). L_(B2) is smaller thanL_(DC) by about the length of BFL section 506. In this example, thedual-camera components that protrude and are visible include only thetop of the lens of the upright camera and top parts of the OPFE. In someexamples, lens sections of the folded camera may also be visible. Ingeneral, a bump may be needed only in areas of the camera where a heightof the upright camera and a height of a section of the folded camera islarger than H_(phone).

Returning now to FIGS. 5A-5C, the reduction of height in the BFL sectioncauses second direction 112 of the folded camera to be closer to a topsurface 510 than to a bottom surface 512 of BFL section 506, creatingasymmetry in the propagation of light rays exiting the lens into the BFLsection. One result of the asymmetry is that an image sensor 514, whichis normally mounted on a board 516 is asymmetrically positioned in the Ydirection relative to the top and bottom sides of the BFL section and ofthe board itself.

FIG. 8A shows a known art image sensor 514 and board 516 as viewed in a+Z direction (along second direction 112). Sensor 514 is, for example, asilicon die that has an optically active part 802 (referred hereafter asactive part 802) surrounded by a part (auxiliary silicon logic) 804considered “non-active” in terms of image\light sensing and referred totherefore as non-active part 804. Active part 802 may be located innon-active part 804 in any position symmetrically or asymmetrically, asknown in the art. Active part 802 is distanced from the top and bottomof board 516 (i.e. in the Y direction shown) by distances marked asD_(TOP) and D_(BOT) respectively. In FIG. 8A, D_(TOP)=D_(BOT)±Δ, where Δis typically 0 to 200 μm. This is a sensor-board arrangement in a knownfolded camera such as camera 100, where active part 802 is typicallypositioned symmetrically or slightly asymmetrically relative to board516 (“slightly” referring to up to 200 μm out of the height (4-6 mm) orabout 0-5% of the PCB height).

FIG. 8B shows an image sensor 514 and board 516 configuration 800according to an embodiment disclosed herein. In configuration 800,active part 802 is positioned asymmetrically relative to board 516 inthe Y direction, and A may be on the order of 100-1500 μm. In this case,the asymmetry of active part 802 relative to board 516 may be on theorder of 100 μm and up to 1-1.5 mm, or about 5%-30% of the PCB height.

The asymmetry results in a surface closer to the sensor's effective rayenvelope and may cause stray light effects on the sensor. For example,in camera 500, top surface 510 is lower and closer to the sensor than atop surface of lens section 504, allowing for light that is entering tobounce off of top surface 510 and be redirected back to the sensor. Tomitigate such effects, an internal surface 518 of top surface 510 of BFLsection 506 is structured to prevent stray light. This may be provided,for example, by a yoke with a special structure and/or with ananti-reflective coating. Alternatively, an internal surface 520 ofbottom 512 of BFL section 506 or both top and bottom internal surfaces518 and 520 are structured to prevent stray light. In certainembodiments, internal surface 518 is uneven and/or has various ridges,so that it is not flat. Alternatively, FIG. 9B illustrates a method forabsorbing or redistributing the light in other directions.

FIGS. 9A-9C show, in various views, a folded camera structure numbered900 according to another exemplary embodiment disclosed herein. Likecamera 500, camera 900 includes an OPFE section 902, a lens section 904and a back focal length (BFL) section 906. The dimensions of the foldedcamera and the different sections may be in the same range as in cameras100 and 500. Camera 900 may include other components with respectivefunctionalities similar to or identical with the components of camera500. Therefore, these components and their respective functionalitiesare not described in detail. Further, camera 900 may include two BFLsections or a split BFL section. Unlike in camera 500, lens section 904in camera 900 has two different sub-sections 904 a and 904 b with twodifferent heights marked H_(L) and H_(L1). Height H_(L) of lenssub-section 904 a is larger than height H_(L1) of sub-section 904 b, toaccommodate at least one lens element 920 with a larger diameter D thanthe diameters of following (in the direction of the image sensor) lenselements (which, for example, have a smaller diameter D₁) For example,H_(L1) may be smaller than H_(L) by 0-3 mm.

While the exemplary embodiment in FIGS. 9A-9C shows a lens section withtwo different heights associated with two different subsections, a lenssection may have more than two subsections with different heights. Forexample, if a lens includes N lens elements (typically N being between 1and 6), then the lens section may include between 1 and N sub-sections.The N subsections may have the same height or different heights H_(LN).In some embodiments with different lens subsection heights H_(LN), theheight may decrease in a step-wise manner from a subsection close to theOPFE (prism) section to a subsection close to the BFL section.

Camera 900 can be included together with an upright camera 204 in adual-camera 1000 as shown in FIGS. 10A-10C. In some examples, the lengthL_(DC) and width W_(DC) of dual-camera 1000 remains similar to those ofdual-camera 600. However, dual-camera 1000 has a lower height not onlyin the BFL section 906 of the folded camera, but also in sub-section 904b of the lens section. Therefore, when dual-camera 1000 is incorporatedin a mobile device such as a smartphone, the lower height of the BFLsection H_(BFL) and of sub-section 904 b H_(L2) enables an even shorterbump length L_(B3).

FIG. 11A shows the dual folded-upright camera of FIGS. 10A-10C includedin a smartphone 1002 in a perspective view. FIG. 11B shows a crosssection with enlarged details of the dual folded-upright camera and thesmartphone. Smartphone 1100 has a bump 1104 protruding over a surface1102. Bump 1104 has a length L_(B3) and a height H_(B2). To clarify, insmartphone 1100, L_(B3) is smaller than L_(B2) in FIG. 7 by about thelength of lens sub-section 904 b and is smaller than L_(FL) by about thelength of BFL section 906 plus the length of lens sub-section 904 b. Themarking of the bump height with “H_(B2)” here and in FIG. 7B does notnecessarily mean that bumps 604 and 1104 have the same height. In thisexample, the dual-camera components that protrude and are visibleinclude only the top of the lens of the upright camera and top parts ofthe OPFE and lens sub-section 904 a of the folded camera. In general, abump may be needed only in areas of the camera where a height of theupright camera and a height of a section of the folded camera is largerthan H_(phone).

Camera 500 can be provided with a flash (e.g. LED) element to obtain afolded camera with flash (or “flash folded camera”). FIG. 12A shows aperspective view, and FIG. 12B shows a side view of a flash foldedcamera 1200. A flash element 1204 may provide an external illuminationsource as needed by the photographed scene, as known in the art. Thereduction of height in camera 500 BFL (H_(BFL)) may be used to houseflash element 1204, i.e. flash element 1204 may be placed on top of topsurface 510. The combined height from the bottom of camera 500 to thetop of flash element 1204 is marked by H_(FLASH), as seen in FIG. 12B.In some cases, H_(FLASH) may be smaller than, or equal to camera 500height (H_(FL)), as seen in FIG. 12B.

Folded camera 1200 may be included with an upright camera 204 to form adual camera. FIGS. 13A-13B show two embodiments of such a dual-camera.In FIG. 13A, a dual-camera 1302 includes an upright camera 204positioned next to flash folded camera 1200 on the optical axis (+Zdirection) toward the side of OPFE section 502. In FIG. 13B, adual-camera 1304 includes an upright camera 204 positioned along camera1200 on the optical axis closer to BFL section 506 side. In dual camera1304, flash element 1204 is positioned between the optical aperture ofcamera 204 and the optical aperture of camera 500.

In other dual-camera embodiments, shown in FIGS. 14A-14C, a camera suchas camera 900 may also be provided with a flash element such as flashelement 1204, which may be positioned on top of BFL section 906 (FIG.14A), on top of lens sub-section 904 (FIG. 14B), or on top of both ofthese sections (FIG. 14C) (partially on top of each section in someembodiments). In all these cases, H_(FLASH) will mark the combinedheight of from bottom of camera 900 to top of flash element 1204.H_(FLASH) may be smaller than or equal to camera height H_(FL). That is,the addition of a flash element does not lead to any protrusion abovethe largest height of the folded camera. Cameras 1400, 1402 or 1404 maybe combined with an upright camera to form a dual camera (not shown).

In yet another dual-camera embodiment numbered 1500 and shown in FIGS.15A and 15B, camera 900 may be combined with an upright camera 204 andflash element 1204, such that the flash element is positioned partiallyabove camera 900 and partially above camera 204.

While this disclosure has been described in terms of certain embodimentsand generally associated methods, alterations and permutations of theembodiments and methods will be apparent to those skilled in the art.The disclosure is to be understood as not limited by the specificembodiments described herein, but only by the scope of the appendedclaims.

What is claimed is:
 1. A folded camera, comprising: a) an optical path folding element (OPFE) section including an OPFE for folding an optical path from a first direction to a second direction, the OPFE section having an OPFE height H_(P) in the first direction; b) a lens section positioned between the OPFE and an image sensor, the lens section having at least one lens section height H_(L) in the first direction; and c) a back focal length (BFL) section extending between the lens section and the image sensor and having a BFL section height H_(BFL) in the first direction, wherein H_(BFL)<H_(P).
 2. The folded camera of claim 1, wherein H_(BFL)<H_(L).
 3. The folded camera of claim 1, wherein H_(L)<H_(P).
 4. The folded camera of claim 1, wherein the lens section includes two subsections, wherein a lens subsection closer to the BFL section has a height H_(L2), wherein H_(L2)<H_(L).
 5. The folded camera of claim 4, wherein H_(BFL)≤H_(L2) and H_(BFL)<H_(L).
 6. The folded camera of claim 5, wherein the BFL section has a top side and a bottom side, wherein the lens section, BFL section and the image sensor share an optical axis, and wherein the optical axis in the BFL section is closer to the top side than to the bottom side, positioning the image sensor asymmetrically relative to a board it is mounted on.
 7. The folded camera of claim 6, wherein the top side has an internal surface structured to prevent stray light from being directed toward the image sensor.
 8. The folded camera of claim 4, further comprising a flash element positioned on the lens subsection closer to the BFL section and having a height H_(FLASH)≤H_(P).
 9. The folded camera of claim 4, further comprising a flash element positioned partially on the BFL section and partially on the lens subsection closer to the BFL section and having a height H_(FLASH)≤H_(P).
 10. The folded camera of claim 4, wherein the BFL section has a top side and a bottom side, wherein the lens section, BFL section and the image sensor share an optical axis, and wherein the optical axis in the BFL section is closer to the top side than to the bottom side, positioning the image sensor asymmetrically relative to a board it is mounted on.
 11. The folded camera of claim 10, wherein the top side has an internal surface structured to prevent stray light from being directed toward the image sensor.
 12. The folded camera of claim 1, wherein the BFL section has a top side and a bottom side, wherein the lens section has an optical axis parallel to the second direction and wherein the optical axis in the BFL section is closer to the top side of the BFL section than to the bottom side of the BFL section.
 13. The folded camera of claim 1, wherein the BFL section has a top side and a bottom side, wherein the lens section, BFL section and the image sensor share an optical axis, and wherein the optical axis in the BFL section is closer to the top side than to the bottom side, positioning the image sensor asymmetrically relative to a board it is mounted on.
 14. The folded camera of claim 13, wherein the top side has an internal surface structured to prevent stray light from being directed toward the image sensor.
 15. The folded camera of claim 1, further comprising a flash element positioned on the BFL section and having a height H_(FLASH)≤H_(P).
 16. The folded camera of claim 1, wherein the lens section has a width W_(L) and wherein W_(L)>H_(L)>H_(BFL).
 17. A dual-aperture camera comprising a folded camera according to claim 1 together with an upright camera.
 18. The dual-aperture camera of claim 17, wherein the upright camera has an upright camera optical axis parallel to the first direction.
 19. A mobile electronic device comprising a folded camera according to claim
 1. 20. The mobile electronic device of claim 19, comprising a bump on a surface thereof, wherein the bump surrounds an area including the folded camera and wherein at least one bump dimension is defined by a folded camera dimension.
 21. A mobile electronic device comprising a dual-aperture camera according to claim
 17. 22. The mobile electronic device of claim 21, comprising a bump on a surface thereof, wherein the bump surrounds an area including the dual-aperture camera and wherein at least one bump dimension is defined by a folded camera dimension.
 23. The mobile electronic device of claim 22, wherein the bump has a length, L_(B), defined along the second direction, wherein the dual-aperture camera has a length, L_(DC), defined along the second direction, and wherein L_(B)<L_(DC).
 24. The mobile electronic device of claim 21, comprising a bump on a surface thereof, wherein the bump surrounds an area including the folded camera and wherein at least one bump dimension is defined by a folded camera dimension.
 25. A method for reducing a bump footprint of a smartphone, the method comprising: a) providing a smartphone; and b) attaching the folded camera of claim 1 to an exterior surface of the smartphone, wherein the folded camera reduces the bump footprint of the smartphone.
 26. The method of claim 25, wherein the bump footprint includes a length L_(B1), a width W_(B1), and a height H_(B1), wherein L_(B1) has a range of 5-50 mm, W_(B1) has a range of 1-20 mm and H_(B1) has a range of 0.05-3 mm.
 27. The method of claim 26, wherein the height of the BFL section, H_(BFL), is lower than the height of the OPFE section, H_(P), such that a shorter bump length L_(B1) is enabled.
 28. The method of claim 27, further incorporating a flash element into the bump footprint.
 29. A mobile electronic device, comprising: a) a dual camera comprising a folded sub-camera and an upright sub-camera, the folded sub-camera having a first optical axis and the upright sub-camera has an upright camera optical axis, the dual camera having a baseline measured between the first optical axis and the upright camera optical axis and having a length L_(DC) measured in a direction along the direction of the baseline; and b) a bump having a length L_(B) measured in the direction along the baseline, wherein L_(B)<L_(DC).
 30. A method of manufacturing a folded camera, comprising: a) providing an optical path folding element (OPFE) section with an OPFE for folding an optical path from a first direction to a second direction, the OPFE section having an OPFE height H_(P) in the first direction; b) providing a back focal length (BFL) section having a BFL section height H_(BFL) in the first direction; and c) providing a lens section having a lens section height H_(L) in the first direction, wherein H_(BFL)<H_(L).
 31. The method of claim 30, wherein the OPFE section has an OPFE section height H_(P) in the first direction, wherein H_(BFL)<H_(P).
 32. The method of claim 30, wherein the lens section has at least two subsections and wherein a lens subsection closer to the BFL section has a height H_(L1), wherein H_(L1)<H_(L).
 33. The method of claim 32, wherein H_(BFL)≤H_(L1) and H_(BFL)<H_(L).
 34. The method of claim 30, wherein the BFL section has a top side and a bottom side, wherein the lens section has an optical axis parallel to the second direction and wherein the optical axis in the BFL section is closer to the top side of the BFL section than to the bottom side of the BFL section.
 35. The method of claim 30, wherein the BFL section has a top side and a bottom side, wherein the lens section, BFL section and an image sensor share an optical axis, and wherein the optical axis in the BFL section is closer to the top side than to the bottom side, positioning the image sensor asymmetrically relative to a board it is mounted on.
 36. The method of claim 35, further comprising asymmetrically placing an image sensor relative to the top side and bottom side of the BFL section. 